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How can we change feeble sound to loud sound?

Answer

Loudness of sound is directly proportional to its amplitude.

Feeble sound can be changed to loud sound by increasing its amplitude.

 

What is Supersonic Speed

Answer

When speed of an object is more than speed of sound,it is said to be travelling at supersonic speed

Example

Bullets, Jet Aircraft travel at supersonic speed

  1. Class 9
  2. Chapter 12 Class 9 - Sound

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.